This invention relates to a shelf for a food display counter, and more particularly to a refrigerated shelf for supporting chilled food items.
The invention involves an improvement upon the refrigerated shelf of the type comprising a flat sheet of metal having an upper surface for supporting chilled food items and a corrugated sheet of metal secured to the underside of the flat sheet thereby forming a plurality of passages for flow of refrigerant therethrough for cooling the upper sheet of metal. A problem with the prior shelf has been that the temperature of the upper surface of the shelf is not uniform throughout the upper surface. In most cases, the upper sheet of metal is of stainless steel, and stainless steel is not a good heat conductor compared to other metals, so that the portions of the upper sheet of metal defining the passages are cooled to a lower temperature than are those portions of the upper sheet of metal away from the passages. The temperature differentials cause ice to form on the upper surface which can cause the chilled food items to "stick" to the shelf. The temperature differentials also prevent the formation of a uniform layer of frost over the upper surface such as is desirable to give the shelf an esthetically pleasing "frosty cold" appearance.
Another problem with the prior refrigerated shelf is that it is not well suited for above-level service (i.e., above the level of the counter top of the food display counter), because it lacks depending side walls refrigerated to substantially the same temperature as the upper surface, and a bottom surface insulated from the passages carrying the refrigerant for preventing the formation of condensation at the underside of the shelf.